Veteran Australian actor John Jarratt has been accused of sexually assaulting a woman on a Sydney beach in the 1970s.

"Police are investigating an allegation of a historic sexual assault on Sydney's eastern beaches," a NSW Police spokeswoman said in a statement on Saturday.

"The allegations were reported to police earlier this month and relate to a matter from the 1970s."

The alleged incident happened while the woman was working in the entertainment industry, Daily Telegraph reported.

John Jarratt. Image: AFP

The Wolf Creek star, 65, "completely denies" the allegations, according to a statement released by his management representative at Ignite Elite Artists.

"John emphatically and completely denies the allegations of sexual assault. These allegations are completely unfounded and untrue."

The Wongawilli, New South Wales, native has been a working actor since 1975, getting his start as Albert Crundall in Peter Weir’s eerie Picnic At Hanging Rock.

More recently, he is best known in the horror genre as Mick Taylor in the Wolf Creek films and current TV adaptation. He also appeared in a minor role in Quentin Tarantino's acclaimed Django Unchained.